1. Department of Respiratory Medicine, Hospital de la Santa Creu i Sant Pau, Institut d'Investigació Biomédica Sant Pau (IIB Sant Pau), Universitat Autònoma de Barcelona, Department of Medicine, Barcelona, Spain.
2. Service of Clinical Epidemiology, Hospital General de Vic, Barcelona, Spain.
3. Integrated Care Unit, Medical and Nursing Direction, Hospital Clínic, IDIBAPS, CIBER de Enfermedades Respiratorias (CIBERES), Universitat de Barcelona, Spain.
4. Lung Management Area, Central University Hospital of Asturias, Oviedo, Spain.
5. Pneumology Department, Hospital Universitario Cruces, Barakaldo, Basque Country, Spain.
6. Service of Pneumology, Hospital de Palamós, Palamós, Girona, Spain.
7. Service of Pneumology, Hospital Arnau de Vilanova, Valencia, Spain.
8. Medical Advisor of Medical Department Chiesi, L'Hospitalet del Llobregat, Barcelona, Spain.